The first thing I noticed browsing my plone site using konqueror is that some of the icons where unreadable. This was using konqueror 3.0 and I do not seem to have that problem with Konqueror 3.1.

You do the administration of your plone site ie adding users, etc by going to www.yourdomain.org/tws/manage and utilising the Zope Management Interface. You can however add content directly through the plone website using plone tools.